Using a plus (+) sign in the e-mail configuration for the built in Hikvision software?

[latropa]

Having a + symbol in an email address is a RFC standard (Email address - Wikipedia) but I can't get the Hikvision setup area to accept it when I try and input an email with a "+" in the Configuration > Network > Advanced Settings > Email area:

Is this just a bug/limitation of the firmware installed on these cameras (DS-2CD2042WD-I V5.5.0 build 170725) or am I maybe missing some other setting I have to change first before it'll accept characters like the plus sign?

I find it really useful for sorting purposes in gmail since google supports adding +whatever to the end of your email address --> Official Gmail Blog: 2 hidden ways to get more from your Gmail address

 

[tangent]

as your link points out, gmail is dot agnostic. I suggest you use this method rather than plus addressing.